Imaging devices such as digital cameras perform auto white balance operations to identify the light source at scene, to white balance the image areas of neutral gray objects, and to correct color of the image areas of colorful objects. For a given imaging device, calibration is utilized to account for part to part variation within the imaging system. For color calibration or white balance calibration, measured data is collected under known light sources such that frames captured by the imaging device can be compared to a reference point. The calibration data can be used to make white balance adjustments, color rendering adjustments or both.